Crystalyte Controllers - Repair and Modification information

[fechter]

From my calculations, the 100k and 300k should be 10k and 30k resp.

Yes, I think you are correct.

Now I have to go back and try to edit all the incorrect diagrams.

 

[Doctorbass]

Why dont you simply use a potentiometer? :wink:

A normal long 10turn pot have enough power rating for that at 72V and worked fine for me!

Fun=
-modified LVC
-modified PWM ramp capacitor
-modified current limit to a pot
8)

I adjusted it by puting a DC clamp meter with peak hold on my power wire during some runs on flat and adjusted it to finally get 40A in ANY time.. during short acceleration burst... my 40A is limited because i installed a 40A fuse and a parallel diode on the controller to avoir fet burning again...the 50A diode is to protect against reversing polarity and is installed after the fuse.

Doc

 

[The7]

i installed a 40A fuse and a parallel diode on the controller to avoir fet burning again...the 50A diode is to protect against reversing polarity and is installed after the fuse.

Unable to view the exact config.
Wonder if you could post an diagram?

 

[Doctorbass]

i installed a 40A fuse and a parallel diode on the controller to avoir fet burning again...the 50A diode is to protect against reversing polarity and is installed after the fuse.

Unable to view the exact config.
Wonder if you could post an diagram?

Here it is:

 

[The7]

Excellent way to protect against reversed battery connection!!

 

[fechter]

That is a common technique. It makes you wonder why they didn't build that into the controller?

 

[The7]

There's a capacitor on the board that controls the ramp up. Stock is 10uf. If you replace it with a smaller one, like 1 uf, it will ramp up much quicker.

It might work to just remove it completely.

On the 48V 20A controller, this is the soft-start cap 10uF.

Has any one changed the soft-start 10uF?
If so, what value did you use?
How do you find after modification?

 

[xyster]

It's 10uF on the other crystalyte controllers too. Doc replaced his with a 2.2uF capacitor.
http://endless-sphere.com/forums/viewtopic.php?t=1765&highlight=ramp

 

[The7]

It's 10uF on the other crystalyte controllers too. Doc replaced his with a 2.2uF capacitor.
http://endless-sphere.com/forums/viewtopic.php?t=1765&highlight=ramp

Yes. Already note.

Try to find what is best value for this ramp (soft-start) cap?es

10 uf gives a ramp time of 0.25 sec.
2.2 uf gives a ramp time of o.056 sec.

Please see my calculation in Doc's post.
http://endless-sphere.com/forums/viewtopic.php?t=1765&postdays=0&postorder=asc&start=15

 

[CGameProgrammer]

Doctorbass, could you post a version of that diagram in which the wires are swapped? What I'm not clear is, let's say Wire A goes from battery positive to controller ground, and Wire B is the opposite of course. Which wire has the fuse? Which direction is the diode? It's not clear to me unless you post a diagram with the wires swapped.

I just ask out of curiosity. I use dual-pole Anderson connectors everywhere which can't be plugged in backwards so I've never encountered this problem, but it seems like an easy mod anyway.

 

[Doctorbass]

I use Anderson 50A connector too.. they aree heavy and solid.

I had the reverse polarity probelm when i had my 6 12V sla. I accidently swapped the blade connector on the sla when i tried many different configurations 3s2p, 6s1p.. etc

To better explain you,

-i start a wire from the pos battery that goes to the fuse
-continu from the fuse next connector to the pos input of the controller
-I start a wire from the neg of the battery and goes to the neg of the controller.

finally i put a diode in non polarised mode in parallel with the controller AFTER the fuse. The fuse will blow even if you connect reversed polarity on that and will let the diode to be polarized that will conduct and blow the fuse before the controller blow because the diode act like a short circuit in this mode and no reverse voltage goes to the controller.... only on the fuse...

Hope i'm understandable here :lol:

Doc

 

[Doctorbass]

Doctorbass, could you post a version of that diagram in which the wires are swapped? What I'm not clear is, let's say Wire A goes from battery positive to controller ground, and Wire B is the opposite of course. Which wire has the fuse? Which direction is the diode?.

Here is for you what you requested:

 

[The7]

The7 wrote:
Did the 2.5s ramp time occur at no-load
Wonder if you could do an simple experiment on your ebike 5304/20?
With the drive wheel off ground, give an quick FULL throttle and note
a) any delay time for the wheel start to rotate;
b) time for it to ramp up to no-load top speed: and
c) the battery current during ramp up.



I did the test myself on AL1020 using 36V at no-load.

Two ways to apply FULL throttle quickly:
1) Twisting the throttle to FULL as fast as I could;
2) Press the brake, turn the FULL throttle. Release the brake and the throttle will be at FULL.

These two ways gave practically the same results .
1) There is a small LAG. Seems to be the order of 0.1s.
2) The speed ramped up to no-load top speed (45 km/h) at a short period. Seems to be the order of 0.5s.
3) An digital ammeter and an analog meter were used to read the battery current. During the ramp up, the ammeter never exceeded 4A. So the current limit (20A) was not reached for such no-load test.

Comment:
1) It seems the order of 0.1s LAG is not desiable.
From memory of motor-cycling in young age, there was no such LAG feeling.
Thinking of changing the 10uF to 1uF may reduce this LAG.
2) When the ebike was loaded (road test), the ebike reached its current-limit (20A) every time at FULL throttle. In such case, the ramp up time (order of several seconds) will be dictated by the current-limit, and the top-speed by the battery voltage.
3) Don't think that there is any other ramp up circuit other than the "soft-start" 10 uF capacitor.

Would like to hear what is your experience.

 

[The7]

No-load test (Drive Wheel OFF Ground)

 

[The7]

Not on this!

 

[Doctorbass]

The7,

when you did your test with no lead and measured the current, are you sure that your ammeter is enough quick to get the high current peak?

I had this problem when I tested with my DC clamp meter and the cycleanalyst. the cycle analyst seems to be much more faster than the Clamp meter!... The meter have a latch and the display is about 0.5s latch..

I will try to measure it using my 50A shunt + a scope :wink: I will post the pic of the phosphore screen...

Doc

 

[The7]

Thanks Doc for reminding me to oscilloscope for the test.

I will use anl DMM(ammter) as an shunt for the scope and do the test again.

Channel 1 to measure the throttle output.
Channel 2 to measure battery current.
See the LAG and ramp-up time between the battery cuurent and the throttle output.

My scope is not a storage scope. Not sure if my camera could capture or noT the traces.

 

[NickF23]

Finally getting round to upgrading my 48 volt controller to 72v. Could anyone recommend some caps? When I look on Digikey there are so many it makes my head spin The 20a 72v model apparently use 160v, 47uF, is this a good bet, is there any other specs I should be looking out for?

http://i106.photobucket.com/albums/m250/NickF23/104_0496.jpg

 

[The7]

Finally getting round to upgrading my 48 volt controller to 72v. Could anyone recommend some caps? When I look on Digikey there are so many it makes my head spin The 20a 72v model apparently use 160v, 47uF, is this a good bet, is there any other specs I should be looking out for?

http://i106.photobucket.com/albums/m250/NickF23/104_0496.jpg

The photo shows that it uses 100V 100uF caps which should be OK for 72V battery.

 

[Doctorbass]

Also, you can buy a cheap picture camera(one use type) and take the caps inside(it is for the flash caps bank). Voltage are around 300V and 100uf or more. you can find some on ebay for 1$ each camera..

Doc

 

[NickF23]

The photo shows that it uses 100V 100uF caps which should be OK for 72V battery.

Thats good to know, are there any other advantages of going with higher uf or voltage though?

 

[NickF23]

Also, you can buy a cheap picture camera(one use type) and take the caps inside(it is for the flash caps bank). Voltage are around 300V and 100uf or more. you can find some on ebay for 1$ each camera..

Doc

ok, you've inspired me to scavenge. Are there any other qualities that I should be looking out for in capacitors, or is it just volage and farads (uf)?

 

[The7]

The photo shows that it uses 100V 100uF caps which should be OK for 72V battery.

Thats good to know, are there any other advantages of going with higher uf or voltage though?

Definitely 160V is better.
100uF seems OK. Larger uF may not improve much.
In your case if you use 160V you need to use a lower uF due to space.

 

[fechter]

ok, you've inspired me to scavenge. Are there any other qualities that I should be looking out for in capacitors, or is it just volage and farads (uf)?

You should also look for "Low ESR" capacitors. "Switching Grade" is another name for them. Lower equivalent series resistance reduces losses and capacitor heating. The filter capacitors in a switching power supply are usually good candidates.

I've seen some capacitors that got quite hot when used in a controller. I've had a couple of them explode on me (with subsequent FET failure :x ). By using low ESR caps, this can be avoided. Using more caps in parallel also reduces the ESR. Higher voltage rated caps tend to have lower ESR also.

Many smaller caps in parallel are better than a single big one. More copper in the leads and more surface area to dissipate heat. A few high frequency multi-layer ceramics in addition to the electrolytics will further reduce losses.

 

[NickF23]

You should also look for "Low ESR" capacitors. "Switching Grade" is another name for them. Lower equivalent series resistance reduces losses and capacitor heating. The filter capacitors in a switching power supply are usually good candidates.

I've seen some capacitors that got quite hot when used in a controller. I've had a couple of them explode on me (with subsequent FET failure :x ). By using low ESR caps, this can be avoided. Using more caps in parallel also reduces the ESR. Higher voltage rated caps tend to have lower ESR also.

Many smaller caps in parallel are better than a single big one. More copper in the leads and more surface area to dissipate heat. A few high frequency multi-layer ceramics in addition to the electrolytics will further reduce losses.

Great info Fetchter,

Is it ok to mix different voltages provided the lowest voltage caps are not exceeded by the battery input voltage? or should all caps be the same?


** sends out message to anyone listening in local area that all unattended psu's and circuit boards are now liable to be raided** 8)